The effects of hypoxia and superimposed hypercapnia or hypertension during hypoxia on brain tissue water content, pH, and electric activity were studied in Sprague-Dawley and stroke-prone spontaneously hypertensive rats. Auditory brainstem responses and sensory evoked potentials were recorded during the experiment as the indices for cerebral oxygen metabolism. The brains were removed immediately, 1 day, and 2 days after hypoxic insult for gravimetric study. The brain water content increased in all groups on the 1st and 2nd days after hypoxia. The percentage change from the control water content increased only on the 1st day in hypoxic rats. In contrast, it increased on both the 1st and 2nd days after hypoxia in hypercapnic or hypertensive rats. The evoked potentials of hypoxic and hypercapnic-hypoxic rats showed that peak latencies were prolonged significantly during hypoxia and recovered 1 and 2 days after hypoxia. The brain tissue pH decreased during hypoxia and recovered after hypoxia. This study suggests that brain edema develops within 2 days of hypoxic insult and that superimposed hypercapnia or hypertension promotes the brain edema.
Sixteen pediatric patients with brainstem glioma were treated with a combination of interferon-β, 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), and radiation therapy (IAR therapy). All patients received 1-1.5 million IU/day of interferon-β intravenously for 1 week of each 6-week cycle. In addition, ACNU (2-3 mg/kg) was given on the 2nd day of each cycle. Conventional focal irradiation (1.5-2 Gy/day for 5 days to a total dosage of 40-60 Gy) was administered beginning on day 3. Patients underwent at least two 6-week cycles. Adverse effects included nausea, vomiting, and myelosuppression, but were mild and transient. Response to treatment was evaluated by the reduction in tumor size measured on postcontrast computed tomographic scans and magnetic resonance images. Responses occurred in 10 of 11 patients with the intrinsic type of brainstem glioma, including three complete and seven partial responses. Two of five patients with exophytic type gliomas partially responded. The median survival was 15.7 months, a remarkable improvement over the natural course of this disease. These results indicate that IAR therapy is a useful primary treatment for pediatric patients with brainstem gliomas.
Favorable and unfavorable prognostic factors were identified in 28 patients surviving for more than 1 year after surgery for metastatic brain tumor and 18 patients surviving for more than 5 years. A high incidence of favorable factors, including neurological grade and location of the brain lesion, indicated significance in the prognosis. A low incidence of favorable factors, including tumor-free interval and presence or absence of extracranial tumor, indicated little significance to the prognosis.
Two rare suprachiasmal carotid-ophthalmic artery aneurysms, one large and one giant, were discovered incidentally. The patients had no visual disturbances. Angiography showed superomedial projection of the sac. The aneurysms were clipped via an ipsilateral pterional approach. A suprachiasmal carotid-ophthalmic artery aneurysm is indicated when preoperative angiography reveals a superomedial carotid-ophthalmic artery aneurysm without visual disturbances. Direct surgery to clipp a suprachiasmal aneurysm should be carried out to prevent rupture of these frequently large aneurysms.
A rare case of subfrontal schwannoma occurred in a 33-year-old male with the chief complaint of headache. Computed tomography demonstrated a low-density mass in the subfrontal region. Magnetic resonance imaging indicated the mass extension into the ethmoidal sinus. The tumor was totally removed via a subfrontal approach. The histological diagnosis was schwannoma. The most likely origin of the tumor is the meningeal branches or anterior ethmoidal nerve.
Transcranial Doppler sonography demonstrated a huge, non-thrombosed intracranial aneurysm in a 62-year-old male preoperatively as abnormal continuous flow, which disappeared after aneurysmal neck clipping. Transcranial Doppler sonography is very useful to assess hemodynamics in the parent artery and the dome of the aneurysm.
An aneurysm of the internal carotid artery associated with Marfan''s syndrome occurred in a 23-year-old female with a 2-year history of a pulsating lesion in the left neck, which progressively increased in size. Left carotid angiography demonstrated a giant saccular aneurysm at the origin of the internal carotid artery. The aneurysm was excised and end-to-end anastomosis performed without postoperative morbidity.
An unusual case of acute subdural hematoma developed after drainage of chronic subdural hematoma in a 71-year-old male. The acute subdural hematoma was located over a membranous layer in the subdural space similar to the outer membrane of the chronic subdural hematoma. Intraoperatively, bleeding from the bridging vein and oozing from the superior sagittal sinus were observed. The membranous layer probably separated from the dura mater following decompression after drainage of the contralateral hematoma, and this separation then damaged the bridging vein and superior sagittal sinus, resulting in the acute subdural hematoma.
A papillary craniopharyngioma localized in the third ventricle occurred in a 45-year-old male. The clinical presentation was unusual and the neuroradiological appearance resembled a choroid plexus papilloma of the third ventricle. The tumor originated from the right anterolateral wall of the third ventricle, forming a discrete mass with prominent papillae formation. The tumor was totally removed by a transcallosal approach without neurological or endocrinological sequelae.
A 45-year-old male presented with a large calvarial mass caused by a malignant fibrous histiocytoma arising primarily from the frontal bone and extending into the intracranial space. Magnetic resonance imaging revealed a well-demarcated, mottled enhanced bulky tumor with several low-signal separations. He underwent extensive tumor and bone removal, followed by radiation therapy. Histological examination showed pleomorphic spindle cells in a storiform pattern. The tissue stained positive for alpha-1-antitrypsin and alpha-1-antichymotrypsin by immunohistochemical techniques.